A cursor display apparatus for displaying a cursor on a display device using an input device has been disclosed, for instance, in FIGS. 2 and 3 of Japanese Patent Laid-Open No. 60-126694 published on July 6, 1985, entitled "Cursor Display Method in Graphic Display", in which the overall image displayed on the display device is divided into several regions, and the direction of the cursor is changed in each divided region. However, the method gives no consideration as to how to change the direction of the cursor display for fine adjustment of the direction of the cursor in an arbitrary region of the display device.
Further, in FIG. 3 of Japanese Patent Publication No. 61-2951 published on Jan. 29, 1986, entitled "Cursor Control Circuit", there is provided a cursor display apparatus including means for moving the cursor by a predetermined amount. However, the circuit provides no way for an operation to fine adjust the cursor while watching the displayed image.
The prior art circuits have a drawback in that they do not provide for easy fine adjustment of the direction of pointing of the cursor, since the cursor is displayed only in one direction in the whole region or the divided region of the display device, and the cursor is not rotatable on the display device.
When it is required to move a cross hair cursor on a display device to a point positioned along a declined line connecting two predetermined points, prior art circuits can not perform such a function, although the cross hair cursor of the prior art can move in a horizontal or perpendicular direction on the display device.